A behavior genetics approach to foreign policy analysis

A Neurobiological Approach to Foreign Policy Analysis: Identifying Individual Differences
The Pennsylvania State University and the United States Studies Centre, Sydney
Abstract: A great deal of foreign policy analyses relies on social and environmental factors, or anecdotal evidence. In seeking to address this problem in a more systematic manner, we move from an investigation centered around state actors to one focused on variation in individual behavior accounting for the combination of social, cultural, environmental, psychological and biological differences. Our proposed approach to the study of political violence requires the integration of methods and skills from geneticists and neuroscientists with those in the behavioral and social sciences. Specifically we seek to introduce an approach to study political violence which : 1) quantifies the effects of genes, environments, and their interaction on behavior; 2) identifies specific genetic and environmental contexts that lead to such behavior; 3) develops a comprehensive model of the biological and social pathways to political violence; and 4) identifies populations under specific circumstances which pose a higher or lower prevalence for any specific genes, neurobiological or environmental mechanisms which pose an increased liability for political violence; 5) develops mechanisms to identify individuals within given populations who are most at risk for committing violence, as well as those most resistant to such action; and 6) creates environmental responses which can mitigate risk among those individuals .
Various scholars have approached the study of foreign policy analysis from a
variety of different frameworks. Some stress the cross cutting cleavages imposed by
different levels of analysis (Starr, 2006), while others emphasize the importance of
examining different topic areas (Hill, 2003) or countries (Beasley et al., 2001). Some
authors acknowledge the critical impact of culture on outcome (Hudson, 2006), while
others point to the decisive influence provided by leaders (Breuning, 2007). Yet, the vast
majority of models in security studies have traditionally stressed the importance of states
and institutions to the relative neglect, if not outright dismissal, of the individual level of
analysis. Indeed, the vast majority of these models essentially ignore the variance in
individuals’ personal attributes, including that of leaders, arguing that structural
incentives provide sufficient explanation for state behavior (e.g. Waltz, 1979). From
these higher order levels of analysis, the source of security threats rest on assessments of
structural and objective indicators, such as an adversary’s military prowess, the nature of
its political and economic institutions, or assumptions regarding the opponent’s
intentions. Each of these perspectives has added important contributions to our
understanding of the various factors which determine foreign policy design,
However, while the focus of study in political violence has historically
concentrated on the state, such state centered approaches have become increasingly
obsolete since the end of the cold war. Events in the last few decades repeatedly
demonstrate that this emphasis must shift to concentrate on individual actors. And if we
direct our attention to an investigation of particular individuals, we must begin to account
for individual differences among and between populations if we are to explain and
predict differences in individual predilections to engage in political violence.
The events of 9/11 provided a tragic illustration of the new challenges confronting
policy makers from non-state actors. Influential actors operate outside the system of
sovereign states, and present threats that are impossible to predict from within the rigid
confines of traditional state-centered perspectives. Indeed, the greatest limitation of such
traditional models lies in their myopic focus on the environment in which states operate,
or a narrowed focus on aspects of the state itself, thereby ignoring the powerful and
independent roles that individuals play in shaping the nature of international politics
One of the increasingly critical features in all aspects of foreign policy analysis is
the focus on the individual actor, whether it is Osama bin Laden, Hosni Mubarak, or
Muammar Quaddifi, and the importance of personal agency in explaining important
variations in international outcomes. As Hudson (2005: 1): writes, “(f)oreign policy
analysis is characterized by an actor-specific focus, based upon the argument that all that
occurs between nations and across nations is grounded in human decision makers acting
singly or in groups.” And traditional state centered theories often provide little help in
seeking to understand the actions or motivation of many aspects of foreign policy which
are clearly driven by individual goals and incentives.
The terrorist attacks on the United States on September 11, 2001 precipitated a
renewed focus on the importance of individual non-state actors in changing world events.
Rather than the previously expected clash between superpowers, a few determined
individual actors crippled the world’s hegemon over the course of a few hours, with
effects arguably more lasting and damaging than any other attack upon the US in the last
half century. Indeed, this very event precipitated a series of high level decisions in
American foreign policy which set the path for the United States to engage in two major
wars which have lasted the better part of a decade, precipitated severe and enduring
economic consequences and which show little signs of either victory or withdrawal.
Prior to 9/11, the notion that the next war would be one fought against individual actors
would have seemed ludicrous, as would the prospect that the United States would face
the kind of economic ruin as a result of extreme defense spending which we precipitated
among the Soviets in the 1980s and 1990s. Yet today, testimony from the Department of
Defense before the House of Representatives declares that the US is “waging a war
against individuals” (Feldman 2006). One of the problems with this challenge, of course,
lies in the fact that without a state, victory becomes ephemeral because there is no one to
surrender for all actors, and as long as a single person with the intention and means of
causing damage survives, the conflict will continue.
Strategic and tactical operations have changed to meet threats from the
“individual”, yet the methods for understanding and properly characterizing individuals
who engage in political violence in current scholarship have not yet caught up, despite
urgent need: “.the same U.S. federal interagency report that documents the significant
increase in funding for combating terrorism and reviews plans and activities by dozens of
civil and military agencies reveals scant evidence of serious effort or funding to
understand why individuals become, or to prevent individuals from becoming, terrorists
We argue this is true because the vast majority of foreign policy analyses which
acknowledge the importance of individuals in determining significant outcomes rely on
purely social and environmental factors, or anecdotal evidence. In seeking to address this
problem in a more systematic manner, we move from an investigation centered around
state actors to one focused on variations in individual behavior which account for the
combination of social, cultural, environmental, psychological and biological differences.
Technological and scientific advances in the last century have given researchers the
ability to explore endogenous influences on behavior. The use of genetic, neurological,
and neurochemical analyses have led to numerous psychological, medical and behavioral
breakthroughs. Despite the valuable information gained however, none of the current
methods in foreign policy carefully interrogate the endogenous underlying bases for
individual differences in behavior. This is unfortunate because there is little question that
complexities of human individual behavior cannot be fully understood without
exploration into all forms of individual variance, including biological, neurological and
genetic mechanisms (Kendler and Eaves 2005). This is true for political actors as well
(Fowler and Schreiber 2008). Recent advances in the study of political and social
behaviors allow for the opportunity to begin rectifying this lacuna in the foreign policy
literature (for a review see Hatemi et al 2011).
Our proposed approach to the study of political violence requires the integration
of methods and skills from geneticists and neuroscientists with those in the behavioral
and social sciences. Specifically we seek to introduce an approach to study political
violence which : 1) quantifies the effects of genes, environments, and their interaction on
behavior that is a threat to national security; 2) identifies specific genetic and
environmental contexts that lead to such behavior; 3) develops a comprehensive model of
the biological and social pathways to political violence; 4) identifies populations under
special circumstances which pose a higher or lower prevalence for genetic,
neurobiological or environmental mechanisms which pose an increased liability for
political violence; 5) develops mechanisms to identify individuals within given
populations who are most at risk for committing violence, as well as those most resistant
to such action; and 6) creates environmental responses which can mitigate risk among
predisposed individuals. Below we provide the details of supporting studies to warrant
such an approach as the basis of developing a more comprehensive model for
understanding the biological and environmental pathways that precipitate political
Advocating for an Individual Approach to the Study of Political Violence
We introduce a powerful approach to the study of individual action in foreign policy
analysis, which has a proven record in other behavioral domains. The approach combines
genetic and biological analyses of individuals in the context of environmental triggers.
Doing so provides a more complete picture of the causes and consequences of political
violence in a world increasingly affected by individual actions and initiatives. This focus
on individual behavioral variation is built upon well-developed models in psychiatric
genetics developed to uncover those forces in the social environment that trigger
predisposed individuals to act in distinct and predictable ways. Focusing on individual
differences interacting with certain environments allows us to develop new tests to
evaluate, assess, and screen threats that nation-states are likely to face in the future, and
offer new suggestions for how best to prevent or mediate them. Certain individuals may
prove more prone to successful recruitment into extremist fundamentalist groups, more
likely to resort to political violence, and less able to resist the appeal of violent
fundamentalist organizations than others given particular exacerbating or ameliorating
conditions. Seeking to identify those most susceptible to commit political violence, when
triggered, offers the possibility for more effective, targeted, programs to help mediate
those very environmental triggers which prove most threatening for those at higher risk
of committing violence. In this way, we provide a unique approach for understanding
individual variation in motivation for engaging in, and responding to, political violence.
In order to explicate the nature of these processes more systematically, we proceed by
describing some of the existing literature designed to explain the sources of political
violence, highlighting some of its remaining limitations. Next we introduce techniques
drawn from behavioral genetics and describe how these models might apply to behaviors
and traits relevant to the study of political violence. We then apply findings derived from
earlier work on precursors to violence to suggest how interacting genes with particular
environmental triggers might help scholars better identify the propensity for violence and
distribution of risk within and across various populations. We hope that this approach
might prove useful in helping to generate more effective prevention and protection
Benefits of a Biological Approach
Individual differences do not exist in a social, political or cultural vacuum.
Rather, culture infuses and imbues meaning and purpose into the dispositions inherent
within given individuals, helping to precipitate different behavior among similar
individuals who develop in different environments. But biology also contributes to such
variance as well, and such an understanding needs to be incorporated into any
comprehensive model designed to explicate the sources of individual variance in
proclivities for engaging in political violence. After all, why do only a small fraction of
individuals residing in repressive political contexts engage in campaigns of terror to bring
A great deal is known about the environmental conditions that determine various
aspects of foreign policy. Still, no matter how comprehensive, explanatory models which
fail to incorporate endogenous motivations for individual action inevitably account for
only a fraction of the total variance of human behavior, suggesting the strong possibility
that environmental determinants of political violence do not tell the entire story (e.g.,
Post, 2005). At a broader societal level, within a given population faced with the same
environmental stressors, how is it that only a handful of individuals can jump on a
grenade to save their comrades? Join an underground army to fight for their beliefs?
Strap a bomb to themselves? Or, run a plane into a building? Thus, in spite of the
obvious resentment among the 1.3 million inhabitants of the Gaza strip, only a very few
actually engage in acts of terrorism. Of approximately 9,000 “Arab Terrorists” detained
by Israeli security forces in Judea and Samaria, less than 400 were deemed to be potential
suicide bombers. Of the approximately 800,000 Catholic residents of Northern Ireland,
Sinn Fein commanded as much as 100,000 votes among Nationalists, but perhaps as few
as 750 were active IRA soldiers. If the focus remains on the environment, then what is it
that differentiates those who take violent action from those who do not among individuals
A primary advantage of a behavior genetic approach to the study of important
topics in foreign policy analysis, such as terrorist motivation and action, lies in its
complimentarity to other extant approaches. Rather than competing with existing
approaches, a neurobiological perspective adds an additional dimension to the
explanatory capacity of existing environment-only models. Such a neurobiological
approach can help leaders and states develop novel ways to limit the development or
recruitment of terrorists, or other violent political activists by helping to more accurately
identify those individuals who pose the greatest risk or uncover the environmental
conditions which offer the greatest protection against such action.
Three critical features would help define such a behavioral genetic model as
applied to political violence. First, it takes a large number of genetic, neurobiological
and environmental factors to create behavior. Second, specific high risk environments
have a stronger effect on individuals more genetically sensitive to specific triggers. And
last, specific individuals at high genetic and social risk tend to self-select into
environments that reinforce their specific vulnerability. No one person is genetically
predisposed to be violent, nor is any one environment going to elicit violence 100% of
the time. Rather, the behavioral genetic approach locates causality at precisely the
intersection of individuals’ unique genetic predispositions and their specific social and
Through this approach, we offer a novel perspective on the role of individual
differences in precipitating political violence. We suggest that scholars who wish to
entertain a more comprehensive and accurate approach to understanding the precipitants
of political violence would be well served by incorporating endogenous factors into their
models of political leadership, behavior and action. Our main argument incorporates
three major elements. First, political violence cannot be fully understood if we ignore
individual differences between people embedded within cultures. Second, locating the
sources of individual variance in willingness to harm others is especially important
because the roots of political violence are multifactorial; they result from interactions
between a large number of biological (genetic) and social (environmental) factors. Third,
these forces might interact in ways which may differ profoundly within and between
Past Approaches to Political Violence
In the traditional political science and policymaking literature surrounding the
origins of political violence, three sets of arguments have been most commonly put forth.
The first typically relate to divisions associated with the allocation of financial and
economic resources and their distribution across society (Barber, 1996; Friedman, 2000).
These arguments often mix with, overlap, and engage in rich dialogue with those which
speak about the clash of cultures and civilizations which can also highlight and further
societal and political fractures between rich and poor, Christian and Muslim, democrat
and autocrat (Huntington, 1996; Fukuyama, 1996). While such arguments certainly help
locate the social stage upon which environmental triggers make their play, they do little
to help explain the reasons why individual actors differ in the way they play their scenes
within the confines of the set onto which they are born.
The third set of arguments focus on the role of the individual in precipitating
political violence. This scholarship sought to find the source of destructive outcomes in
dysfunction origins and suggested that political violence remains rooted in individual
psychopathology. While this approach considers individual differences, it has remained
restricted by a vision refracted through the prism of abnormal psychology and
psychopathology, rather than expanded by a conception of the desire or willingness to
resort to political violence as part of a continuum of normal human aggressive action and
behavior in response to environmental triggers. For example Post (1998) argues that
terrorist suffer from particular personality disorders, and their particular psychology
drives them to commit terrorist acts. Post argued that individuals with particular
personality characteristics were more likely to be drawn to terrorist groups as well.
However, this view has been challenged by findings that most terrorists are in fact normal
and that there is no such thing as a particular personality type which characterizes
terrorists. Crenshaw (1981) concluded that “the outstanding common characteristic of
terrorists is their normality.” Separate studies involving Palestinian suicide bombers ,
and members of the Irish Republican Army, the Algerian National Liberation Front
(FLN) , West German terrorists, and Italian terrorists, found that those who engage in
terrorist acts are not mentally ill, emotionally disturbed, or depressed, but rather exist in
the normal range for most typical DSM conditions (Rasch, 1979; Jager, Schmidtchen,
and Sullwold, 1981; Segal 1987; Sullwold, 1981; Jager, 1981; Ferracuti and Bruno, 1981;
Moreover, insofar as more recent Middle Eastern terrorism is concerned, despite
public sentiment that suicide terrorists are “crazed cowards bent on senseless destruction”
no recognizable psychopathology is present (Atran’s 2003). On average, they are similar
in education level and economic class to the general population. Ruby (2003) concludes
that “.terrorists are not dysfunctional or pathological; rather, terrorism is basically
another form of politically motivated violence that is perpetrated by rational, lucid people
Indeed, one of the best arguments for the relative normality of terrorists lies in the
efficacy of their action; severely mentally ill people are not sufficiently well organized,
disciplined and controlled to plan and conduct large scale actions such as devastating
terrorist acts require. Organized actors typically cannot accomplish these things by
relying on psychotics. As Atran argues, “Recruiters for groups sponsoring terrorism
acts tell researchers that volunteers are beating down the doors to join. This allows
terrorist agents to choose recruits who are intelligent, psychologically balanced, and
socially poised. Candidates who want mostly virgins in paradise . are weeded out.
Those selected show patience and the ability to plan in subtle, quiet ways that don't draw
attention. Al Qaeda, especially, is rarely in a hurry. It can wait years and then strike
From an objective view, it makes sense that most terrorists should appear normal
along personality dimensions which are consistent across cultures, and such individuals
should remain fairly normally distributed within populations. After all, in order to
become an effective terrorist, a person must retain at least a semblance of an ability to
engage in efficacious, organized action, or his or her terrorist activities would only meet
with failure. Moreover, psychopathologies, such as anti-social disorders, schizophrenia,
and other personality disorders affect only a small portion of the population, and are
present in all societies. Although such individuals may engage in maladaptive behaviors
or behaviors inconsistent with societal norms, such as extreme violence, such behaviors
are rarely predictable or strategic in nature among such individuals, thus defining their
Thus, although some scholars have attempted to locate vulnerability for terrorist
action in psychological disorders, and others in normality, neither model adequately
interrogates the source of individual variance in such action. After all, if terrorists emerge
unduly from particular segments of the population, it would be worthwhile to understand
further the ways in which they diverge from the normal population. On the other hand, if
they in fact appear psychologically inseparable from the broader population as defined by
traditional normal and abnormal measures, it remains critical to determine which forces
precipitate such action, since most people do not engage in terrorist activity. Yet despite
these divergent approaches to understanding individual variance in terrorist proclivity, to
date there has not been any empirical investigation of the genetic, biological or
neurological differences that may exist among and between individuals prone to engage
in terrorist acts and those who refrain from such activity even under identical
environmental pressures. Models drawn from behavior genetics offer an ideal avenue of
The field of behavior genetics has been perhaps most involved in the exploration
of endogenous sources of individual differences and human behavior. For readers
unfamiliar with the behavior-genetic paradigm, we outline the elements briefly here. The
basic issues are discussed in far greater detail, with examples, by Eaves et al. (2005),
Kendler (2005), Carey (2003), and Neale and Cardon (1992).
The underlying foundation of the research program engages both endogenous and
exogenous factors and explicitly acknowledges that genes operate in conjunction with
environmental factors during human development (i.e., from infancy to maturity). It is
critical to be explicit that genes do not “determine” any behavior or trait. Rather, in
simple terms, they provide the platform for the synthesis of proteins which then trigger a
series of chemical processes which have neurological, cognitive and emotive implications
among others effects, dependent on environmental cues. These neurobiological changes
then inform and influence behavior in interaction with environmental stimuli. While
genes are static, gene expression is not, and depends on the behavior of the individual, the
environments the individual is exposed to, and the interaction with others (Johnston and
Edwards 2002). For example, dopamine appears critically involved in such behaviors
as aggression, novelty seeking and reward dependence. Certain dopamine genotypes lead
to higher or lower levels of dopamine uptake and regulation. Yet children with the exact
same variant on a dopamine gene, can also manifest different levels of dopamine
influenced behavioral aggression in a given modern context depending on whether or not
they received adequately sensitive parenting and external social support during critical
formative years . In this way, their gene expression or regulation of dopamine can be
altered during childhood by sensitive parenting, but interacts with modern circumstance
to guide behavior. Individuals who did not receive such care display more problem
behaviors, including higher rates of attention deficit disorder, while those who are
fortunate enough to receive attentive care show lower levels of such behavior than
children without that particular variant of the gene (Belsky et al., 2007).
To reiterate, the behavior-genetic paradigm does not find if “something is
genetic”. Rather, the individual is a responsible agent for his/her behavior, yet this
approach also remains cognizant of the reality that ignoring a priori one critical source of
individual differences, genetic variation, may have grave consequences for our ability to
model variance in individual behavior once certain processes are triggered. If, for
example, political violence bears any similarity to other kinds of extreme behavior,
including violence (Volavka, 1999), anti-social behavior (Lyons et al, 1995) , aggression
(Chen et al, 2005; Filley, 2001), deviance (Booth and Asgood 1993), conduct disorder
(Eaves et al, 1997; Foley et al, 2004), and substance use disorders, understanding the role
of genetic differences may be critical to understanding why one individual is more likely
to become a suicide bomber in the face of foreign occupation while another is not.
Potential Genetic Precursors to Political Violence
The vast range of behavior-genetic studies demonstrates that to understand fully
human behaviors we cannot ignore genes any more than we can ignore a person’s
environment. As noted above, this certain holds true for violence. Treating genes and
environment in isolation from one another overlooks essential characteristics of human
behavior. Human development results from a conversation between genes and the
environment that modifies the expression of genes and shapes the environment in which
development occurs. Humans have a remarkable facility to create, evaluate, and modify
their environment through extended parental care and familial cohabitation and other
complex social groups. Such reciprocal effects generate relationships between genetic
and environmental influences that are frequently referred to as “gene-environment
Susceptibility to political violence can be conceived in terms using models and
techniques from the well established study of behavior genetics, just like any other
psychological trait. However for political violence, the “line” of what exactly constitutes
problematic behavior changes with the times and power structures within the
international community. For example, throwing rocks at American soldiers in the
United States would be considered extremely deviant behavior. However, Palestinians
doing the same thing to Israeli soldiers in the West Bank is far more common. Therefore,
careful operationalization of the operative concept remains crucial in undertaking any
Individuals clearly differ in their vulnerability or propensity to engage in political
violence. The greater a person’s liability, the more likely they are to engage in violent
Figure 1: Interaction of Genes and Environment in Risk to Political Violence P{V}.
Figure 1 represents two hypothetical individuals with differing genetic constitutions. In
the absence of exposure to a specific environmental “trigger” (such as growing up in the
Gaza strip) (E-) both individuals (G1 and G2) have a low probability of performing an act
of terrorism (P{V}). However, when the environment is changed (E+), on average one of
the two “genotypes” (G2) responds with a higher probability of violence.
The general notion that there are observable threshold effects in the interactive
relationship between an individual’s genetic makeup and their social environment enjoys
strong support in existing genetic models of violence, aggression, and other precursors to
political violence . Three decades of research investigating individual risk for complex
psychological and psychiatric traits of body and mind suggests that no one “gene” or
single “environmental” factor holds the key to understanding behavior. Rather, unique
configurations of many genes and environmental factors are necessary to understand
Space constraints prevent us from reviewing every relevant study which might
provide novel approaches or allow us to gain a better of understanding of the genetic and
neurobiological influences which might be involved in precipitating political violence
(see Appendix 1 for a summary table). However, we highlight the relevance and
significance of a few important studies below to provide some illustrations of how work
in this area might proceed . Hormones in the body help regular cognition and emotion.
Overall, it appears that genes in the glutamate family and in the adrenic systems,
including some which influence the dopaminergic and serotonergic systems, are
implicated in the expression of behavioral offensive and impulsive aggression (Brodkin
et al. 2002; Brown et al. 1982; Chen et al 2005; Placidi et al 2001).
In addition, serotonin, while more commonly known for the treatment of
depression, is centrally involved in an enormous number of important processes,
especially related to mood, metabolism and memory (Davidge et al. 2004; Jensen et al.
2009). In particular, serotonin has long been believed to be involved in aggressive forms
of violence and aggression; for example, variance in serotonin activity accounted for 5%
of the divergence in violent outcomes in criminality (Retz et al., 2004). However, it is
important to note that for any gene, hormone, or neurobiological mechanism, the
relationship is not a simple linear casual pathway. That is, decreased serotonin does not
equal increased violence (Olivier & van Oorschot, 2005). Rather, complex genetic and
myriad environmental factors influence the relationship between serotonin,
environmental triggers, and the extent, duration and lethality of aggressive violence.
De Boer et al. (2009, 52) presents one of the most compelling examples of the
relationship between genes and environment in explaining the emergence of violence,
and how violence and aggression are regulated through genetic systems. These processes
differ between individuals, and are also affected in different ways by specific
environmental stressors, which can leads to different behavior in those with the same
genotype, or even within the same person over time acting under different circumstances.
This study showed that mice with certain kinds of serotonin receptors appear much more
likely to react aggressively after being exposed to violence in their environment. Thus,
based on genotype, mice differed in their behavior; mice with a particular genotypic
variant on their serotonin receptors responded aggressively more often and more quickly,
and were more persistent, indiscriminating and more likely to injure others. Simply put,
these mice were more prepared to learn aggressive behavior once they witnessed it,
versus others mice who were not so genetically predisposed. Like those who themselves
have been the victim of child sexual assault, or witnessed domestic violence in their own
home are more likely to become abusers themselves, some victims go on to become
perpetrators while others do not; some of this difference in response may be attributable
to genotypic variance among individuals, just like in the mice. Such a model could easily
be juxtaposed to larger human environments as well. In conditions of relative peace,
individuals more susceptible to decreased serotonin and dopamine activity may appear
similar to everyone else. However, place those individuals under stress in an environment
prone to violence such as Iraq, the West Bank or Gaza strip and they are most at risk to
engage in violence themselves, due to the combination of the overwhelming stressful and
violent world they are living in and their own genetic liability.
Human studies have also found similar relationships between aggression and
serotonin regulation (Brown et al., 1982). Overall, individuals with a low activity form of
serotonin manifest increased impulsivity, explosive violence, and higher levels of
testosterone (Virkkunen et al, 1994). For example, Placidi et al. (2001) found that those
with a lifetime history of higher rates of aggression had lower levels of serotonin.
Interestingly, they noted a complex relationship between the lethality of aggressive and
suicide attempts and serotonin levels, such that high lethality attempters showed
significantly lower levels of serotonin than those who had exhibited lower lethality
attempts, who did not differ in their levels from normal controls.
Reif et al. (2007) further elucidated the relationships between specific genetic
variants and aggressive behavior by finding a relationship between adverse childhood
events and other parts of the serotonergic pathway. First, polymorphisms in monoamine
oxidase (MAOA) and serotonin (5-HTT) transmitters were found to correlate with violent
behavior. However, adverse childhood events and the presence of MAOA exerted
independent effects on its emergence. People with MAOA who had nurturing childhoods
and relatively stable lives can be peaceful, as can those without MAOA who have
stressful lives. However, each alone could precipitate violence as well under varying
levels of provocation, and the combination proved particularly likely to precipitate
violence. The influence of the MAOA variant only erupted in later life violence, but
required the prior contribution of adverse childhood events in order to manifest. In
addition to MAOA also precipitating behavioral aggression under conditions of
provocation (McDermott et al., 2009), higher levels of testosterone (Booth and Mazur,
1998; Johnson et al., 2006) also appear highly predictive of the propensity for aggression
in both individuals and across populations.
Other work has suggested a role for dopamine pathways in precipitating violence
(Chen et al 2005), as well as other aspects of cognition, including planning, as well as
reward and novelty seeking (Backman et al. 2000; Cropley et al. 2006; Noble et al. 1998;
Reeves et al. 2005), two behaviors related to impulsive violence under certain conditions
(Hess et al 2009). Dopamine is particularly noteworthy not only because of its
relationship to aggression levels, but also because genetic variants of critical dopamine
receptors differ markedly in systematic ways across population groups by region
Applying a Behavioral Genetic Model to Political Violence
The literature discussed above suggests three critical ways in which behavioral
genetic approaches may inform our understanding of variation in individual levels of
political violence. The first is to help observers better ascertain those most likely to
engage in political violence under specific environmental conditions within a given
population. Second, if specific genetic markers, such as dopamine for example, are found
to relate to certain types of violence under certain conditions, behavioral genetics might
help identify the relative propensity per region for violence by population given a certain
stimulus, such as a foreign occupation. That is, certain genetic and hormonal systems
vary by population in systematic ways and given suitable environments, these differences
may result in different percentages of a population engaging in violent activity. We
recognize that accurately predicting these differences may not yet be possible, but it is
worth considering at least at a theoretical level that defense and relief efforts may be best
predicted by inclusion of population differences at both environmental and biological
levels. Third, by being able to identify genetic variants relative to violent behavior under
a given condition, we might also be able to develop strategies which might reduce the
effects of genetic liability to engage in violence, and thereby reduce the overall potential
Identifying Individuals and Population Risk to Engage in Political Violence
Different environments pose different levels of risk for the potentiating violence.
We are under no pretense that particular individuals are genetically predisposed to
violence. Rather, the global conditions create the stage to precipitate violent activity
under particular circumstances. Rather, we suggest that certain environmental conditions,
including but not exclusive to economic pressure, lack of opportunity, political strife,
oppression, restrictive borders, the death of one’s children, maddrassas, and other such
propellants create the possibility to instigate any human reaction, including violence. Yet,
individuals differ remarkably in how they respond to those conditions. Overall, violence
may increase, under such conditions, but not everyone engages in it, even though the
most extreme circumstances would appear to invite such behavior. Genetic factors
constitute unlikely proximate causes for political violence. However, they may contribute
to placing individuals at increased risk for engaging in political violence when exposed to
stressful and threatening environments. Huntington (1996), Friedman (2000) and others
who focus on cultural clashes and economic stresses as potentiators of the probability of
conflict at a population level are certainly correct. However, we can also investigate those
social and biological factors which create the greatest likelihood for producing a
conflagration of violence at the individual level when individual risks stews in a soup of
rage and humiliation to generate an environmental powder keg.
One of the best ways to explore these dynamics is to examine previous hot spots
in which the local environment remained synonymous with violence for decades, but
individual family members are divergent in engaging in violent action. Once a place
becomes safe in the wake of peace agreements, as for example has largely occurred in
Northern Ireland, it becomes possible to examine different related individuals in the
context of the same negative environment to see whether and how certain individuals are
more prone to violence in response to the same precipitant, such as witnessing the violent
death of a loved one at the hands of a political opponent.
This kind of investigation allows a novel form of methodological approach to
provide prophylactic treatment of high risk populations, rather than merely wait to pay
the costly price of a search for perpetrators after occasions of violence. Such an
approach can thus allow scholars and policy makers to learn more from previous
experiences and engagements, and to use extended family designs, to help identify, and
more effectively intervene, between experiences of oppression, brutalization, humiliation,
or other triggers, and the incidence of political violence. This can be done, for instance,
through a systematic examination of siblings who may have experienced the same
precipitating event, such as watching a parent brutally murdered, whereby one brother
took up arms against the offender, and another decided to work through peaceful
channels for a resolution to overall levels of violence. A behavior genetics approach can
leverage precisely the intersection of experience and biology to highlight the fluids which
both inflame and extinguish the fires of foment. In this way, we propose using the same
kind of methodological model used to explore complex social behavior such as the study
of impulsive aggression in mice described above to further explore the context of
political violence in humans among those at greatest environmental risk.
Through this process, we can determine whether certain genetic markers correlate
more strongly with engaging in violence, just as dopamine levels impulsivity appear to
correlate with risk and reward seeking. And, as noted with dopamine, the prevalence of
some of these genetic markers can be shown to differ geographically across populations.
Thus, if we find important markers which raise the risk for certain populations to react
with higher frequency to environmental assaults with violence, this information can aid in
national security policy expectations for social disobedience, upheaval and unrest, as well
as prospects for non-violent versus violent proclivities to potentiate social change. These
propensities can hold tremendous implications for national security and future foreign
Can We Use Behavioral Genetic Designs to Identify Prevention Strategies?
If political violence bears any similarity to other forms of aggression, then the
potential to mitigate genetic vulnerability with environmental support is possible. Genetic
influence is not destiny, any more than environmental influences are. Social treatment is
quite effective for both genetic and environmental vulnerabilities. One such example of
this is presented by Boomsma et al. (2000). Figure 2, reproduced from their study, shows
that genetic influences for deviant behavior can be modified by the social environment.
Specifically, childhood deviant behavior, including violence, has been found to be highly
heritable in numerous studies. However, in Calvinist homes, no such finding exists. That
is, there is no difference between a population of identical twin pairs (MZ), who are
genetically similar, and a population of fraternal twin pair (DZ), who are as genetically
similar as any non twin sibling pair, in deviant behavior. However in non-religious
homes, a marked difference does exist between identical and fraternal twins in their
susceptibility to deviant behavior. In other words, in homes with a strict Calvinist
upbringing, genetic disposition does not affect the likelihood that the person will engage
in deviant behavior. This suggests that environmental support can constrain or induce
biological tendencies for violent behavior in general. Strong environmental socialization
thus can shape, control and constrain the effect of genetic predisposition in ways that do
not exist when such environmental forces are absent or diminished.
Figure 2. Interaction between genes and environment in liability to complex behavior: the Effect of Strict Religious Upbringing on Expression of Genetic Differences in Behavioral
Notes: MZ refers to monozygotic, or identical twins, and DZ, refers to dizygotic, or fraternal twins.
The analogy with the etiology of phenomenon such as political violence is clear.
In an otherwise “benign” or “nurturing” environment, genetic differences in liability to
political violence may be present but not expressed. However, in malign or non
supportive environments, perhaps resulting from exposure to abuse or injustice, genetic
differences are expressed. Indeed, such responses may even be adaptive from an
evolutionary perspective because they motivate action which attempts to recalibrate the
balance of power between actors. Once again, awareness of relative susceptibility to
political violence according to both genetic and environmental factors can help identify
and support those most at risk for developing violent tendencies before they manifest
Previous work has primarily examined only the social and environmental
precursors to violence and ignored the source of what makes each individual unique.
While the existing environmental work is critical, it leaves unexplained a large portion of
the variance in determining the difference between those who will work peacefully
through the political process, and those willing to take violent action to bring about the
outcomes they desire when faced with the same environmental stressors. By focusing on
individual differences in biological structures, both brain and genetic, in interaction with
specific environmental triggers, we can obtain more accurate and detailed additional
measures to evaluate both the relative risk for political violence within particular cultures
as well as provide insight into the specific individuals most likely to actively participate
We have provided a gene-environment (behavioral-genetic) approach to
understanding the human factors underlying individual variation in motivation for
engaging in adversarial and violent behavior such as terrorist action. Here we discuss
terrorist action and political violence as an important aspect of human agency in foreign
policy analysis, with important potential outcomes for international relations, but by no
means imply that this factor is the only one that matters in foreign policy decision making
or that it represents the only area of foreign policy analysis to which behavior genetic
theories and methods can be applied. Rather, we argue that any exploration into
individual differences, including leadership, elite behavior, bureaucratic, legislative or
other arena could benefit from the method introduced here. The proposed model will
allow us to examine the influence of endogenous human factors on individuals’ behavior
and to predict which individuals are most likely to become adversaries under particular
A neurobiological approach should not lead observers to be any more pessimistic
about the prospects for positive intervention than more traditional approaches which
focus equally challenging environmental risk factors. In fact, these strategies overlap in
their implications, suggesting various ways to influence environmental precipitants to
reduce the risk of violence. However, a neurobiological approach can provide more
effective targeting by identifying both those individuals at most risk for engaging in
violence, but also those circumstances which are most likely to trigger such action in
those who are most biologically vulnerable to it. In addition it may identify those
environments which offer protective influences on those same genetic liabilities. A
neurobiological approach places importance on developmental factors, such as nutrition
and parenting, which can permanently affect the lifetime propensity for engaging in
violent behavior. Children born during times of drought or famine, for example, or those
who grow up in war zones or were exposed to radiation, may be permanently altered in
ways not captured by approaches which focus on income, resources, or education. Some
of these changes, such as anxiety, or those precipitated by radiation, can be genetically
transmitted into the next generation. In addition, such individuals may then act to
permanently change their environment, through migration or violence, in ways that might
decisively influence the next generation’s capacity to flourish. States which recognize
the influence of such factors can work to mitigate these risks, not under the guise of
minor actions of humanitarian intervention, but as major forces which can precipitate
generational rises in violent action among those affected.
The political relevance of such an approach appears obvious and ubiquitous.
Small differences in some basic biological features, such as baseline levels in certain
hormones or genetic tendencies, might be used to inform our understanding of cross-
cultural differences in basic behaviors, such as risk-taking, aggression or cooperation. We
remain only the beginning of such work, but if we take these arguments seriously, the
deeper foreign policy implications remain profound as well. If orphans, or children of
women who have suffered from famine, can produce inter-generational effects in risk-
propensity or the tendency to engage in political violence, based on in utero deprivations,
or post natal caring, for example, then the political gains from imposing sanctions which
might, for example, deny food aid can produce very long term deficits and exert
potentially very long term political effects which run counter to the interests we are trying
to pursue by imposing those restrictions. By using deprivation strategies to put pressure
on leaders today, we may directly be reducing prospects for peace with future generations
if they become biologically more prone to respond to risk at lower levels of provocation
as a result. In such a way, states can destroy their chances for long term rational
negotiation by pursuing short-term, and short-sighted, strategies which privilege
immediate material incentives while ignoring the deeply enduring biological
ramifications of various foreign policy strategies.
A neurobiological approach can help identify those individuals within civil
society whose exposure to violence and innate sense of vengeance places them at higher
risk for engaging in political violence themselves. And, by assessing individuals’ innate
propensity to engage in political violence, this approach also offers the prospect of
developing a strategy to intervene in the sequence of individuals’ exposure to extremist
violence and subsequent recruitment into fundamentalist extremist organizations. This
includes the potential to identify processes which may be beneficial in preventing those
individuals primed by pro-fundamentalist activities from actually taking violent action.
The recruitment strategies of terrorist organizations are predicated on exploiting
individual’s vulnerabilities to engage in violent action against particular adversaries.
Being able to identify individual differences that place certain people at greater risk for
committing acts of violence constitutes a first step in designing effective intervention
Introducing genetic differences into an understanding of the sources of foreign
policy action in no way eliminates or undermines the importance of cultural or
environmental context in explaining outcomes of importance. Indeed, only through
extreme environmental conditions are genetic liabilities present. In addition, comparing
the findings across divergent populations offers an opportunity for culture specific
perspectives as well. Our approach places the analysis of individual genetic and
biological attributes in the context of specific environmental triggers. Doing so provides
a more complete picture of the causes for, and consequences of, individual willingness to
engage in political violence in a world increasingly affected by non-state actors.
By focusing on individual differences in biological structures, both brain and genetic,
in interaction with specific environmental triggers, we can obtain more accurate and
detailed measures to evaluate both the relative risk for political violence within particular
cultures as well as providing insight into the specific individuals most likely to be the
purveyors of such violence. Developing tests to evaluate, assess and screen threats will
facilitate identifying those individuals most prone to successful recruitment into extremist
fundamentalist groups, those most likely to deploy political violence if provoked, and
importantly, those individuals most likely to resist, and work against, the appeal of
The implications of this approach for purposes of national defense remain striking
and staggering. Conducting behavioral genetic study of political violence provides a
unique approach to understanding the root causes of political violence propagated by
individuals. This approach allows us to examine not only the causes of political violence,
but also their consequences on a larger societal level by exploring the effects of violence
on both the perpetrators and their victims. In addition, this perspective allows us to
identify those individuals whose exposure to violent and traumatic events would make
them more susceptible to post traumatic stress disorder, suicide, substance abuse, and
violence against others. Such assessments can provide a filter between exposure and
recruitment into fundamentalist extremist organizations whose purpose is designed to
exploit and deploy individual vulnerabilities in service of violent actions. We view such
fundamentalist actions as one, but not the only example of the larger class of
phenomenon of political violence. Identifying individual differences which place certain
people at risk for committing acts of violence, and thus inevitable places others at risk for
sustaining injury, constitutes the first step in designing effective intervention programs to
Both policymakers and academics already have a pretty good idea of the pressures
and environments that create the most political violence. A glance around the globe
informs any thoughtful observer of the areas which have traditionally been most prone to
violence, either because of resource pressures, governmental failures, or other factors.
We know how to identify these areas and regions. What we are not so good at knowing is
which individuals within those regions are most likely to react to those environmental
pressures and stresses with violence, as opposed to peaceful action. We are also not so
good at identifying the environmental buffers that we might employ to reduce the liability
of individuals engaging in such behavior. Being able to identify such individuals and
environments can help target more effective and efficient interventions which can lower
the risk for triggers to spark into violent flame.
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Background Briefing For those who care about the human future. All the confused talk and violence: what does it mean? Dr. Al Sears; Quote: ". Will this change? To understand why activities such The pharmaceutical giant Wyeth is being sued over its as mentioned above are allowed, even encouraged, synthetic hormone drugs Premarin and Prempro. They first learn basic logic. The c